Recent advances in image sensor technology have led to remarkable increases in the resolution of digital cameras. Similar advances have occurred in display technology. Consumer-grade digital still cameras and displays are now capable of capturing and presenting multi-megapixel images.
The spatial and temporal resolution of image sequences that are captured by video cameras, however, is still much lower than the available sensor and display resolution. For example, while high-definition television (HDTV) screens are capable of displaying images of 1280×720 pixels at 60 frames/sec, the resolution of standard NTSC video cameras is no better than 720×480 pixels at about 30 frames/sec. One reason for this limitation is the low readout rate (in pixels/sec) of the image sensor devices used in these cameras. In other words, image sensors can generally provide their maximal spatial resolution only at low temporal resolution (i.e., low frame rate), or conversely, maximal temporal resolution at low spatial resolution. The maximal readout rate of the image sensor is generally insufficient to support maximal spatial and temporal resolution simultaneously.
There are methods known in the art for compressing a video stream in order to reduce the data rate required to transmit images at a certain spatial resolution and frame rate. Such methods, however, are applicable to a sequence of video frames after acquisition and do not address the restriction imposed during image acquisition by the limited readout rate of the image sensor.